Observation Date: 02/15/2014
Accessed terrain via Lolo pass on snow machines. We got to the top of the ridge around 11am and discussed options and conditions.
It was warm with overcast skies.
There wasn’t any wind but we could see cornices and wind loading to lookers right (North Facing).
New Snow: 3-6″
Our group consisted of two skiers both with formal avalanche education (Level I and II). We reached the location with thoughts of skiing moderate terrain. Both members had read the most recent missoulaavalanch.org advisory (2/14/14) and were aware of the considerable advisory. We found a moderate angle slope (22 degrees and almost due east aspect) roughly 7000′ and dropped to a 33-36 degree convex roll over where we performed slope stability tests. Test results were CTM23Q1 and ECTN21Q1 with the primary instability 18-20 inches from the surface. Skier A skied the slope and lost a ski at the bottom of the concave slope. That skier then started hiking up to retrieve the ski when a loud audible whoomph was heard. Immediately following, a slab avalanche remotely released and propagated roughly 500′ at a depth of 4-4.5′ deep. The avalanche ran approximately 700-800′ and overran skier A at the bottom of the slope. Skier A was covered and carried 100′ before being deposited with head near the surface. Skier A was able to self rescue and communicate via radio to Skier B. Skier A was uninjured and able to hike up slide path to skier B. Skis, poles and other gear were lost during the slide. The slide ran on a very deep instability consisting of clean ice crust that was not observed in slope assessment.
Observer: Kyle Sillars